98SEBlackMax

iTrader: (9)

Well over the winter/spring when I did my engine bay rebuild, chassis foaming the front of the car was part of my project.

http://forums.maxima.org/oldpost.php...65&postcount=7

(click for that for the details on how I did the foaming)

Now that I've driven and raced the car on a road course I would like to post up my opinions and feelings on it. As far as road course cornering is concerned I have to say one word...

UNDERSTEER

The front end is ALOT stiffer and with the original & tired rear suspension/bushings I had a bad feeling that was going to happen. I ran out of time to do the rear suspension before Maxus and got the car on the road 5/26 then left on 5/30.

As for positive results the intial turn in and lane change of this car is amazing, it doesn't feel sloppy and rides alot more smoothly. However I don't believe the foam is 100% responsible for this. I replaced all the bushings with ES ones, replaced every other bushing that ES doesn't make for us, and installed a rebuilt '99 SE steering rack. (carsteering.com)

Also there was no noticeable change with the ES bushings in regards to the ride harness or increased road noise that I hear about. IMO the foam definitly helps quelch alot of these little problems and makes the car overall much more fun to drive.

Another experiment I did was to fill the center crossmember with 8 pound density foam. This was to see if it would stop the vibration from the PR motor mounts I had installed a while back. Suffice to say I've had several people sit in my car and people say it idles like a stock Maxima. The downside is that when the car is not moving and running it smells like burning hash browns. The Y pipe sits to close to the center crossmember and starts to toast the foam. Covering the Y pipe with header wrap stopped the smoke and reduced the smell by alot, but IMO it's not sufficent. Im going to get another crossmember from a junkyard and swap it out for a comparison to the foamed one.

Later on this Summer I will foam the rear of the car and rebuild the suspension to see what difference it would make. As of right now I don't want to even look at my Maxima, were on a trial seperation.

BEJAY1

iTrader: (19)

Thanks for posting. I wonder what filling just the rear portion and lower rails would do? Stiffen the heck out everything rear of the CG but keep the front soft..

98SEBlackMax

iTrader: (9)

Im debating if I should use 8 pound density on the back end to make it more stiff, the front I used 4 pound stuff. It just costs alot more and adds a bit more weight. Also this stuff is permenant !!!

Just a mod list of what has been done-

AGX struts (2/8)
Eibach springs
All 4th gen ES bushings
PR motor mounts
WSP 2nd gen stage 1,2,3 SFCs
Filled side mounts with 94a Flexane
Stillen RSB
weight reduction

irish44j

iTrader: (38)

interesting....I am more interested in the longitudinal rails, myself, to alleviate the severe body flex the 5th gens are cursed with...

too bad you did all the foam, bushings, etc at once - makes it tough to know what did what, and how much effect each thing had. I always try to do one at a time (even when I have 3 things ready to be installed) and at least do a quick testdrive to see the difference individually.

Of course in your case that would have been tough to do!

98SEBlackMax

iTrader: (9)

It's tough to do things one at a time when the engine bay is down to bare metal and has to be back together in a few weeks for Maxus.

Trust me I was going to do coilovers and a full chassis foam but ran out of time and money. But for now im going to do one thing at a time and see how it does.

Also the foam is hidden, sanded, and the imprefections filled with bondo. You auto crossers couldn't tell its there.